[Devel] Re: [PATCH 01/18] io-controller: Documentation

Gui Jianfeng guijianfeng at cn.fujitsu.com
Tue May 5 20:16:04 PDT 2009


Vivek Goyal wrote:
...
> +	mount -t cgroup -o io,blkio none /cgroup
> +
> +- Create two cgroups
> +	mkdir -p /cgroup/test1/ /cgroup/test2
> +
> +- Set weights of group test1 and test2
> +	echo 1000 > /cgroup/test1/io.ioprio
> +	echo 500 > /cgroup/test2/io.ioprio

  Here seems should be /cgroup/test2/io.weight

> +
> +- Create two same size files (say 512MB each) on same disk (file1, file2) and
> +  launch two dd threads in different cgroup to read those files. Make sure
> +  right io scheduler is being used for the block device where files are
> +  present (the one you compiled in hierarchical mode).
> +
> +	echo 1 > /proc/sys/vm/drop_caches
> +
> +	dd if=/mnt/lv0/zerofile1 of=/dev/null &
> +	echo $! > /cgroup/test1/tasks
> +	cat /cgroup/test1/tasks
> +
> +	dd if=/mnt/lv0/zerofile2 of=/dev/null &
> +	echo $! > /cgroup/test2/tasks
> +	cat /cgroup/test2/tasks
> +
> +- At macro level, first dd should finish first. To get more precise data, keep
> +  on looking at (with the help of script), at io.disk_time and io.disk_sectors
> +  files of both test1 and test2 groups. This will tell how much disk time
> +  (in milli seconds), each group got and how many secotors each group
> +  dispatched to the disk. We provide fairness in terms of disk time, so
> +  ideally io.disk_time of cgroups should be in proportion to the weight.
> +  (It is hard to achieve though :-)).

-- 
Regards
Gui Jianfeng

_______________________________________________
Containers mailing list
Containers at lists.linux-foundation.org
https://lists.linux-foundation.org/mailman/listinfo/containers




More information about the Devel mailing list